JP2019043642A - Multilayer film for packaging, packaging body and packaging container - Google Patents

Abstract

To provide a multilayer film for packaging, a packaging body and a packaging container which can be resealed after being opened once and obtain the packaging body which can be clearly determined to be once opened.SOLUTION: A multilayer film for packaging 1 includes at least four layers including a base material layer (A) 11, an adhesive resin layer (B) 12, a release resin layer (C) 13 and a seal resin layer (D) 14 laminated in this order. The adhesive resin layer (B) 12 contains as a main component a styrenic thermoplastic elastomer having a peak value of a loss tangent (tan δ) measured at a frequency of 10 Hz by a dynamic viscoelasticity measurement at -35°C or more. The seal resin layer (D) 14 contains a resin composition in which at least two types of a high melting point resin (d-1) and a low melting point resin (d-2) are mixed. A melting point difference (Tmd1-Tmd2) between the melting point (Tmd1) of the high melting point resin (d-1) and the melting point (Tmd2) of the low melting point resin (d-2) is 13°C or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a multilayer film for packaging, a package, and a container for packaging, for example, a multilayer film for packaging that can package stored products such as food and medicine, a package and a container for packaging.

  In the past, when packaging containers such as food, cosmetics and medicines, in consideration of the fact that they can not be used all at once, in order to avoid deterioration due to oxidation, moisture absorption and drying, they may be resealed after being opened once. A peelable / resealable packaging film has been proposed (see, for example, Patent Document 1).

Unexamined-Japanese-Patent No. 2006-213053

  However, in the packaging film described in Patent Document 1, when the contents are packaged and resealed, it may be difficult to determine whether the package has been opened once. For this reason, when a food or the like is packaged using the packaging film described in Patent Document 1 and displayed at a supermarket or the like, it is difficult to determine whether or not the product is once opened and resealed. Even if it is mischief or foreign matter mixing, it may not be understood. Thus, while the conventional packaging film is resealable, it is difficult to determine whether or not it has been opened once, and when it is made a package and a packaging container, it is opened once. There is a need for a reclosable packaging multilayer film that can be clearly determined whether or not it is.

  The present invention has been made in view of such circumstances, and is a multilayer film for packaging which can be re-sealed after being opened once, and a package which can be clearly determined to be opened once is obtained, It aims at providing a package and a container for packing.

  As a result of intensive investigations in view of the above problems, the present inventor has a base material layer (A), an adhesive resin layer (B), a release resin layer (C) and a seal resin layer (D), and the adhesive resin layer (B) It has been found that the above problems can be solved by the multilayer film for packaging having two kinds of resins in which the sealing resin layer (D) has a predetermined melting point difference with a peak value of loss tangent of at least a predetermined value. It came to complete. That is, the present invention is as follows.

  The multilayer film for packaging according to the present invention comprises at least four layers in which a base material layer (A), an adhesive resin layer (B), a release resin layer (C) and a seal resin layer (D) are laminated in this order, The adhesive resin layer (B) is mainly composed of a styrenic thermoplastic elastomer having a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement at -35 ° C. or higher, and the sealing resin layer ( D) contains a resin composition in which at least two types of resin (d-1) and resin (d-2) are mixed, and the melting point (Tmd1) of the resin (d-1) and the resin (d-2) The melting point difference (Tmd1 to Tmd2) from the melting point (Tmd2)) is characterized by being 13.degree. C. or more.

  In the multilayer film for packaging according to the present invention, the content of each of the resin (d-1) and the resin (d-2) in the resin composition is preferably 25% by mass or more.

  In the multilayer film for packaging according to the present invention, in the sealing resin layer (D), the resin (d-1) and the resin (d-2) preferably each contain a polyolefin resin.

  In the multilayer film for packaging according to the present invention, the base layer (A) is a layer mainly composed of at least one selected from the group consisting of ethylene-vinyl acetate copolymer saponified product and polyamide resin. It is preferable to include at least one layer.

  In the multilayer film for packaging according to the present invention, it is preferable that the release resin layer (C) contains, as a main component, at least one selected from the group consisting of a polyamide resin and a cyclic polyolefin resin.

  In the packaging multilayer film according to the present invention, the thickness of the sealing resin layer (D) is preferably 2 μm or more and 20 μm or less.

  A package according to the present invention is characterized by including the above multilayer film for packaging.

  The package according to the present invention is preferably for food.

  The package according to the present invention is preferably for sanitary materials.

  The packaging container according to the present invention is characterized by using the above-mentioned package.

  According to the present invention, it is possible to realize a multilayer film for packaging, a packaging body, and a packaging container which can be resealed after being opened once, and a package which can be clearly determined to be opened once is obtained.

FIG. 1 is a schematic cross-sectional view of a packaging multilayer film 1 according to an embodiment of the present invention. FIG. 2: is explanatory drawing of the peeling mechanism at the time of sealing the multilayer film for packaging and the to-be-adhered film 2 which concern on embodiment of this invention. FIG. 3 is an explanatory view of a first peeling mechanism of the multilayer film for packaging and the adherend film according to the embodiment of the present invention. FIG. 4 is an explanatory view of a second peeling mechanism of the multilayer film for packaging and the adherend film according to the embodiment of the present invention. FIG. 5 is an explanatory view of a combination of the first peeling mechanism and the second peeling mechanism of the packaging multilayer film and the adherend film according to the embodiment of the present invention. FIG. 6 is a schematic cross-sectional view at the time of sealing of the package according to the embodiment of the present invention. FIG. 7 is a schematic cross-sectional view at the time of peeling of the package according to the embodiment of the present invention. FIG. 8 is a view showing a specific example 1 of the packaging container according to the embodiment of the present invention. FIG. 9 is a view showing a specific example 2 of the packaging container according to the embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings. The present invention is not limited at all by the following embodiments.

  In addition, in this specification, "it is comprised as a main component" is the meaning which accept | permits including other components in the range which does not prevent the effect | action and effect of resin which comprise each layer. Furthermore, this term does not limit the specific content rate, but it is 50% by mass or more and 100% by mass or less, preferably 70% by mass or more and 100% by mass or less, more preferably 85% by mass of the whole component % Or more and 100% by mass or less, particularly preferably 95% by mass or more and 100% by mass or less.

(Multilayer film for packaging)
FIG. 1 is a schematic cross-sectional view of a packaging multilayer film 1 according to the present embodiment. As shown in FIG. 1, the multilayer film 1 for packaging comprises a substrate layer (A) 11, an adhesive resin layer (B) 12 provided on the substrate layer (A) 11, and an adhesive resin layer (B). And 12.) A release resin layer (C) 13 provided on 12 and a seal resin layer (D) 14 provided on the release resin layer (C) 13. That is, the multilayer film 1 for packaging has at least four layers in which the base material layer (A) 11, the adhesive resin layer (B) 12, the release resin layer (C) 13 and the seal resin layer (D) 14 are laminated in this order. Is included.

  The adhesive resin layer (B) 12 contains, as a main component, a styrene-based thermoplastic elastomer having a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement at -35 ° C. or higher. Adhesive resin layer (B) 12 has joined base material layer (A) 11 and exfoliation resin layer (C) 13 via the adhesive resin layer (B) 12 concerned. The release resin layer (C) 13 can be released from the adhesive resin layer (B) 12 when heat sealed under predetermined conditions.

  The seal resin layer (D) 14 contains a resin composition in which at least two types of a high melting point resin (d-1) and a low melting point resin (d-2) are mixed. The melting point difference between the high melting point resin (d-1) and the low melting point resin (d-2) between the melting point (Tmd1) of the high melting point resin (d-1) and the melting point (Tmd2) of the low melting point resin (d-2) What (Tmd1-Tmd2) is 13 degreeC or more is used. The multilayer film 1 for packaging has a pressure-sensitive adhesive resin layer (B) 12 by sealing the sealing resin portion (D) 14 under a predetermined heat sealing condition with a film to be adhered (parting base material) to be an adhesion partner. Or it becomes peelable with the sealing resin layer (D) 14.

  Next, the first peeling mechanism and the second peeling mechanism in the packaging multilayer film 1 according to the present embodiment will be described with reference to FIGS. FIG. 2 is an explanatory view of a peeling mechanism at the time of sealing the multilayer film for packaging according to the present embodiment and the adherend film, and FIG. 3 is a multilayer film for packaging according to the present embodiment and the adherend film FIG. 4 is an explanatory view of a first peeling mechanism according to the present embodiment, and FIG. 4 is an explanatory view of a second peeling mechanism of the multilayer film for packaging and the film to be adhered according to the present embodiment. It is an explanatory view of the combination of the 1st exfoliation mechanism and the 2nd exfoliation mechanism of the multilayer film for packing concerned, and the film to be adhered concerned.

  As shown in FIG. 2, the packaging multilayer film 1 according to the present embodiment is bonded to the adherend film 2 by heat sealing or the like. The to-be-adhered film 2 includes a base material layer 21 and a seal resin layer 22 provided on the base material layer 21. The packaging multilayer film 1 and the adherend film 2 are adhered by fusion via a heat seal portion 31 provided by heat sealing.

  The adhesive film 2 is not particularly limited as long as it can be heat-sealed with the multilayer film 1 for packaging. For example, as the base material layer 21 of the film to be adhered 2, a film or sheet containing a rigid resin such as a polyester resin or a polypropylene resin can be used. The seal resin layer 22 preferably contains a polyolefin resin. Moreover, the to-be-adhered film 2 may have another barrier resin layer etc.

  The thickness of the adherend film 2 is not particularly limited as long as it can be combined with the packaging multilayer film 1 into a package and a packaging container. For example, as the film to be adhered 2, a film of 50 μm to 500 μm can be suitably used. By setting the thickness of the adhesive film 2 to 50 μm or more, sufficient rigidity can be obtained as a base material of the package and the packaging container, and by setting the thickness to 500 μm or less, the thermoformability becomes good and it is used as a bottom material It also becomes possible.

  In the present embodiment, when peeling the multilayer film 1 for packaging and the film to be adhered 2 by changing the temperature condition at the time of heat sealing, changing the peeling mechanism to either the first peeling mechanism or the second peeling mechanism it can. As shown in FIG. 3, in the case of using the first peeling mechanism, the packaging multilayer film 1 and the film to be adhered 2 have a melting point (Tmd2) or more of the low melting point resin (d-2) and a high melting point resin (d−). Heat seal (hereinafter, also referred to as "heat seal condition A") at a temperature lower than the melting point (Tmd1) of 1). As a result, the interlayer strength between the sealing resin layer (D) 14 of the multilayer film 1 for packaging and the sealing resin layer 22 of the film to be adhered 2 fused by heat sealing is the adhesive resin layer (B) of the multilayer film 1 for packaging And lower than the interlayer strength of the release resin layer (C). Thereby, since the seal resin layer (D) 14 of the multilayer film 1 for packaging functions as an easy peel layer, when the non-fusion part 1A other than the heat seal part 31 is held and peeled off, the multilayer film 1 for packaging Peeling occurs at the interface between the seal resin layer (D) 14 and the seal resin layer 22 of the adherend film 2. When it peels by this 1st peeling mechanism, it can not re-seal the multilayer film 1 for packaging, and the to-be-adhered film 2.

  As shown in FIG. 4, in the case of using the second peeling mechanism, the package multilayer film 1 and the adherend film 2 are heat sealed at a melting point (Tmd1) or higher of the high melting point resin (d-1) (hereinafter referred to as “ Heat sealing condition B ". As a result, the interlayer strength between the sealing resin layer (D) 14 of the packaging multilayer film 1 and the sealing resin layer 22 of the film to be adhered 2 fused by heat sealing is the adhesive resin layer (B) 12 and the peeling resin layer (C) The interlayer strength of 13 is increased, that is, the packaging multilayer film 1 is firmly heat-sealed with the adherend film 2. Thereby, when it is going to peel off the multilayer film 1 for packaging from the film to be adhered 2 holding the non-fusion part 1A, the seal resin (D) 14 of the multilayer film 1 for packaging and the seal resin layer 22 of the film to be adhesive 2 As a result, the adhesive resin layer (B) 12 of the multilayer film for packaging 1 and the peeling resin layer (C) 13 peel off. As a result, since it peels between adhesion resin layer (B) 12 and exfoliation resin layer (C) 13, it pressure-press-bonds the location where multilayer film 1 for packaging and adhesion film 2 exfoliated with a hand and a finger etc. By doing this, adhesion can be made between the exposed surface 12A of the adhesive resin layer (B) 12 and the exposed surface 13A of the release resin layer (C) 13. Therefore, when it peels by this 2nd peeling mechanism, resealing of the multilayer film 1 for packaging and the to-be-adhered film 2 is attained.

  The first peeling mechanism shown in FIG. 3 and the second peeling mechanism shown in FIG. 4 may be used in combination. As shown in FIG. 5, in this case, the heat seal area 31 of the multilayer film 1 for packaging and the adhesive film 2 is heat sealed under the heat sealing condition A and heat sealed under the heat sealing condition B. And Thereby, in the heat seal part 31, the first heat seal part 31a and the adhesive resin layer (B) 12 which are areas where the seal resin layer (D) 14 and the seal resin layer 22 peel off at the interface between the seal resin layer and the seal resin layer 22 It can be provided together with the second heat-sealed portion 31 b which is a re-sealable region between the resin layers (C) 13. Thus, according to the above embodiment, by combining the two peeling mechanisms of the first peeling mechanism and the second peeling mechanism, it is possible to reseal even after being opened once, and once opened. The multilayer film 1 for packaging which can be clearly judged is obtained. Hereinafter, the configuration of each layer of the packaging multilayer film 1 will be described in more detail.

  The thickness of the multilayer film for packaging 1 is not particularly limited. The lower limit of the thickness of the packaging multilayer film 1 is preferably 20 μm or more, more preferably 40 μm or more, and still more preferably 50 μm or more from the viewpoint of film productivity. The upper limit of the thickness is preferably 100 μm or less, more preferably 80 μm or less, and still more preferably 70 μm or less from the viewpoint of the heat sealability with the non-adhesive film 2.

(Base material layer (A) 11)
The base material layer (A) 11 contains a thermoplastic resin as a main component. The thermoplastic resin is preferably selected in consideration of the type of resin used as the main component of the adhesive resin layer (B) 12 and the release resin layer (C) 13. As the thermoplastic resin, since the melt extrusion temperature is in the range of about 180 ° C. to 300 ° C., a thermoplastic resin that can be melt extruded within this range is suitably used. Examples of the thermoplastic resin include olefin resins such as ethylene resins, propylene resins and cyclic olefin resins, amide resins, and saponified ethylene-vinyl acetate copolymers (hereinafter also referred to as "EVOH"). And ester resins, styrene resins and carbonate resins. One of these thermoplastic resins may be used alone, or two or more thereof may be used in combination as a mixed resin composition. The base material layer (A) 11 may be a single layer or a multilayer.

  The thermoplastic resin is, for example, polyethylene terephthalate (hereinafter, also referred to as "PET") resin, polybutylene terephthalate (hereinafter, also referred to as "PBT") resin, from the viewpoint of molding processability, production cost, transparency, etc. Preferred are polyester resins, ethylene-vinyl acetate resins, nylon (hereinafter also referred to as "Ny") resins. Among these, PET resins are preferable from the viewpoint of imparting rigidity to the multilayer film 1 for packaging, and EVOH resins are preferable from the viewpoint of imparting barrier properties.

  Other polyester resins include polypropylene terephthalate resin, polyethylene isophthalate resin, polyethylene naphthalate resin, polybutylene naphthalate resin, polyethylene terephthalate / isophthalate copolymer resin, 1,4-cyclohexanedimethanol unit, all glycol unit amount Also listed are low-crystalline or non-crystalline polyethylene terephthalate resins containing 15 mol% or more and 50 mol% or less in the unit, aliphatic polyester resins represented by polyethylene / neopentyl terephthalate copolymer resin and polylactic acid-based resin, etc. Be

  In addition, a thermoplastic polyester elastomer having a high melting point and high crystallinity aromatic polyester as a hard segment, and an amorphous polyester or an amorphous polyether as a soft segment may be appropriately mixed with the polyester resin. These elastomers may be used alone or in combination of two or more.

  As the EVOH resin, those having an ethylene content of 29 mol% or more are preferable, those having 32 mol% or more are more preferable, and those having 47 mol% or less are preferable, and those having 44 mol% or less More preferable. The EVOH resin preferably has a degree of saponification of 90% or more, more preferably 95% or more. By selecting the grade in which the ethylene content rate and the degree of saponification fall within the above range, the gas barrier properties and mechanical strength of the multilayer film for packaging 1 can be made favorable. These EVOH resins may be used as a mixture.

  Examples of Ny-based resins include aliphatic polyamide polymers such as ring-opening polymers of cyclic lactams, polycondensates of aminocarboxylic acids, and polycondensates of dicarboxylic acids and diamines. Examples of aliphatic polyamide polymers include homopolymers of ε-caprolactam referred to as 6 nylon (6 Ny), polyhexamethylene adipamides referred to as 66 nylon (66 N y), and copolymers thereof Some 6-66 nylons (6-66 Ny) etc. are mentioned. Further, as the aromatic polyamide polymer, a resin or the like containing, in the molecular chain, 70 mol% or more of a polyamide structural unit consisting of xylylene diamine and α, ω fatty acid dicarboxylic acid having 6 to 12 carbon atoms, etc. It can be used. As such resin, for example, homopolymers such as polymetaxylylene adipamide, polymetaxylylene pimeramide, polymetaxylylene azeramide, polyparaxylylene aceramide and polyparaxylylene decanamide, metaxylylene / For example, copolymers of paraxylylene adipamide, copolymers of metaxylylene / paraxylylene pimeramide, copolymers of metaxylylene / paraxylylene aceramide, copolymers of metaxylylene / paraxylylene cepacamide, etc. Copolymers may be mentioned. As such a copolymer, aromatic nylon (MXD-Ny), semi-aromatic nylon etc. are mentioned, for example. One of these may be used alone, or two or more may be mixed and used in combination.

  In the case of imparting a function to the multilayer film 1 for packaging, the substrate layer (A) 11 includes one or more layers mainly composed of a saponified ethylene-vinyl acetate copolymer in order to impart gas barrier properties. Is preferred. Moreover, in order to provide pinhole resistance to the multilayer film 1 for packaging, it is preferable that the base material layer (A) 11 contains one or more layers which have a polyamide-type resin as a main component. However, when base material layer (A) 11 is made into a multilayer structure, the delamination strength of each resin layer which constitutes a multilayer is between adhesion resin layer (B) 12 and exfoliation resin layer (C) 13 An adhesive resin that is greater than the delamination strength is appropriately selected and used.

  Other components may be appropriately added to the base material layer (A) 11 as long as the gist of the present invention is not impaired. Other components include, for example, components such as an antifogging agent, an antistatic agent, a heat stabilizer, a nucleating agent, an antioxidant, a lubricant, an antiblocking agent, a releasing agent, and a UV absorber. When the base material layer (A) 11 has a multilayer structure, other components may be added to only a specific layer, and other components may be added to all layers.

  The thickness of the base material layer (A) 11 is not particularly limited. The thickness of the base material layer (A) 11 is preferably 10 μm or more, more preferably 30 μm or more, and still more preferably 50 μm or more, from the viewpoint of molding processability and manufacturing cost. The thickness is preferably 90 μm or less, more preferably 70 μm or less, and still more preferably 50 μm or less.

(Adhesive resin layer (B) 12)
The adhesive resin layer (B) 12 is a layer for providing a resealable property. The adhesive resin layer (B) 12 is mainly composed of a styrene-based thermoplastic elastomer (b) having a temperature at which the temperature at which the peak value of loss tangent (tan δ) is measured at a frequency of 10 Hz by dynamic viscoelasticity measurement is -35 ° C or higher. Is a layer configured as The adhesive resin layer (B) 12 is a pressure-sensitive adhesive resin layer (B) 12 and a peeling resin layer (C) 13 exposed at the time of peeling if the temperature at which the peak value of loss tangent (tan .delta.) Is shown is -35.degree. And practical re-sealability is expressed only by pressure bonding with a finger. Here, it is inferred that the resealability is also influenced by the viscoelastic characteristics at normal temperature, in particular, the value of the loss tangent (tan δ). Moreover, as the adhesive resin layer (B) 12, it is more preferable that the value of loss tangent (tan δ) at normal temperature be 0.1 or more (the upper limit is usually about 0.6). The upper limit of the temperature at which the peak value of the loss tangent (tan δ) of the styrenic thermoplastic elastomer is usually 10 ° C. or less from the characteristics as an elastomer. Furthermore, the package using the multilayer film 1 for packaging may be used also in low temperature environments, such as a refrigerator installation represented by a refrigerator. Therefore, the temperature range showing the peak value of loss tangent (tan δ) is -35 ° C or more, preferably -25 ° C or more, and preferably 5 ° C or less, and is 0 ° C or less Is more preferred.

  The styrene-based thermoplastic elastomer is preferably a copolymer of styrene and a homolog of styrene such as α-methylstyrene and a conjugated diene, and a hydrogenated derivative thereof. Here, as a conjugated diene which comprises a conjugated diene part, a 1, 3- butadiene, an isoprene, a 1, 3- pentadiene etc. are mentioned. These conjugated diene moieties may be contained in the copolymer singly or in a mixture of two or more. However, the thermal stability and weatherability of the double bond mainly consisting of vinyl bonds in this conjugated diene moiety is extremely poor, and in order to improve this, 80% or more of the double bond, preferably 95%. It is preferable to use what added hydrogen above.

  The temperature at which the peak value of loss tangent (tan δ) of a styrenic thermoplastic elastomer is mainly determined by the styrene content and the vinyl bond amount of the conjugated diene moiety (for example, 1, 2 bonds in the case of butadiene, 1 in the case of isoprene) , 2 bond and 3, 4 bond (depending amount). The styrene thermoplastic elastomer preferably has a styrene content of 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and 25% by mass or less. The content is preferably 20% by mass or less, and more preferably 15% by mass or less. Moreover, as a styrene-type thermoplastic elastomer, that whose vinyl bond amount of a conjugated diene part is 40 mol% or more is preferable, and what is 50 mol% or more is more preferable.

  Examples of styrene-based thermoplastic elastomer resins include styrene / isoprene / styrene block copolymer, styrene / butadiene / styrene block copolymer, styrene / isoprene block copolymer, styrene / butadiene block copolymer, styrene / ethylene propylene / Styrene-based random copolymers such as styrene block copolymers, styrene-based block copolymers such as styrene-ethylene-butylene-styrene block copolymers, styrene-ethylene-butylene-brene, ethylene-butylene-olefin crystal block copolymers, etc. It can be mentioned. One of these may be used alone, or two or more may be used in combination.

  Other resin and component may be added to the adhesive resin layer (B) 12 as appropriate, as long as the gist of the present invention is not impaired. Examples of other resins and components include low crystalline or amorphous olefin resins, softeners, oils (mineral oil), stabilizers (antioxidants etc.), liquid paraffin and the like.

  The thickness of the adhesive resin layer (B) 12 is preferably 2 μm or more, more preferably 3 μm or more, and more preferably 5 μm or more from the viewpoint of resealability after unsealing and production cost etc. Is more preferably 10 μm or more, particularly preferably 50 μm or less, more preferably 40 μm or less, and still more preferably 30 μm or less.

(Peeling resin layer (C) 13)
The peeling resin layer (C) 13 is a sealing resin layer (D) 14 when it is heat-sealed with the adherend film 2 (heat sealing condition B) above the melting point (Tmd1) of the high melting point resin (d-1) described above. In particular, if the interlayer configuration between the adhesive resin layer (B) 12 and the release resin layer (C) 13 is smaller than the interlayer strength between the adhesive film 2 and the seal resin layer 22 of the adherend film 2 It is not limited. The release resin layer (C) 13 may be a single-layer resin layer or a multi-layer resin layer, as desired.

  The release resin layer (C) 13 is a layer containing as a main component at least one selected from the group consisting of polyamide resins and cyclic polyolefin resins. As the polyamide resin, non-crystalline nylon resin is preferable. As an amorphous nylon resin, a brand name "Gribory (registered trademark)" (made by Emskemy Japan) etc. are mentioned, for example. By using the amorphous nylon resin and the cyclic polyolefin, the adhesion between the adhesive resin layer (B) 12 and the release resin layer (C) 13 is improved, and a good re-peel strength can be obtained.

  The thickness of the release resin layer (C) 13 is preferably 1 μm or more, more preferably 1.5 μm or more, and still more preferably 2 μm or more, from the viewpoint of obtaining good re-sealability. Further, from the viewpoint of preventing the film residue after peeling, the thickness is preferably 10 μm or less, more preferably 5 μm or less, and still more preferably 4 μm or less.

(Sealing resin layer (D) 14)
The seal resin layer (D) 14 contains a resin composition containing at least two of a high melting point resin (d-1) and a low melting point resin (d-2).

  The seal resin layer (D) 14 is heat-sealed with the adherend film 2 at a melting point (Tmd2) or more of the low melting point resin (d-2) and less than the melting point (Tmd1) of the high melting point resin (d-1) In the case of A), the sealing resin layer (D) 14 and the sealing resin layer 22 of the film to be adhered 2 peel off at the interface to act as an easy peel layer. The seal resin layer (D) 14 acts as a strong heat seal layer when heat sealing (heat seal condition B) with the adherend film 2 is performed at or above the melting point (Tmd1).

  As the sealing resin layer (D) 14, the melting point difference (Tmd1-Tmd2) between the melting point (Tmd1) of the high melting point resin (d-1) and the melting point (Tmd2) of the low melting point resin (d-2) is 13 ° C. or more There is no particular limitation if it is. The melting point difference (Tmd1 to Tmd2) is preferably 14 ° C. or more, more preferably 15 ° C. or more, from the viewpoint of stably acting the seal resin layer (D) 14 as an easy peel layer.

  The sealing resin layer (D) 14 may be a single-layered resin layer or a multi-layered resin layer, as desired. As the high melting point resin (d-1) and the low melting point resin (d-2) of the seal resin layer (D), for example, a polyolefin (PO) resin and a polyethylene terephthalate (PET) resin are used. Further, as the high melting point resin (d-1) and the low melting point resin (d-2), for example, ethylene-vinyl acetate copolymer (EVA) based resin, polyethylene (PE) based resin, polypropylene (PP) based resin Particularly preferred are polyolefin (PO) resins such as modified PO resins.

  Ethylene-based resins include ethylene-based resins such as ultra-low density polyethylene, linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), EVA, ethylene -Methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-glycidyl methacrylate copolymer, ethylene- Ethylene-based copolymers such as vinyl acetate-glycidyl methacrylate copolymer, ethylene-maleic anhydride copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer, metal-neutralized ethylene-acrylic acid copolymer, Ethylene-methacrylic acid A metal neutralized product of the polymers. One of these ethylene resins may be used alone, or two or more thereof may be used in combination.

  The PP-based resin may, for example, be a propylene homopolymer (homo PP) or a copolymer of propylene and another α-olefin such as ethylene or butene. The copolymer may be a random copolymer (random PP) or a block copolymer. The stereoregularity may be any of an isotactic structure, a syndiotactic structure, an atactic structure, a stereo block structure, and the like. One of these may be used alone, or two or more of these may be mixed and used in combination.

  The sealing resin layer (D) 14 contains at least two of the high melting point resin (d-1) and the low melting point resin (d-2) described above, and the melting point difference (Tmd1 to Tmd2) is 13 ° C. or more. Other resins and components may be added as appropriate as long as the components are contained.

  The content of the high melting point resin (d-1) is preferably 25% by mass or more, more preferably 30% by mass or more, and still more preferably 50% by mass or more. The content of the high melting point resin (d-1) is preferably 75% by mass or less, more preferably 70% by mass or less, and still more preferably 65% by mass or less. When heat sealing (heat seal condition A) is performed with the adhesive film 2 and the melting point (Tmd2) or more and the melting point (Tmd1) or more by the compounding ratio of the high melting point resin (d-1) being 25 mass% or more, the seal The resin layer (D) 14 functions as an easy peel layer. Moreover, when it heat-seals with the to-be-adhered film 2 (heat seal conditions B) above melting | fusing point (Tmd1) by being 60 mass mass or less, it heat-seals with the to-be-adhered film 2 firmly.

  The melting point (Tmd1) of the high melting point resin (d-1) is preferably 80 ° C. or higher and 100 ° C. or higher from the viewpoint of preventing the inner and outer surfaces of the film from blocking each other when wound up as a film. The temperature is more preferably 110 ° C. or more. The melting point (Tmd1) of the high melting point resin (d-1) is preferably 200 ° C. or less, more preferably 180 ° C. or less, and further preferably 170 ° C. or less from the viewpoint of heat sealability. preferable.

  The low melting point resin (d-2) is not particularly limited. The low melting point resin (d-2) is preferably contained in an amount of 25% by mass or more and 60% by mass or less. When the content of the low melting point resin (d-2) is 25% by mass or more, heat sealing (heat sealing condition A) is performed with the adhesive film 2 and the melting point (Tmd2) or more and the melting point (Tmd1) The seal resin layer (D) 14 functions as an easy peel layer. In addition, when the content of the low melting point resin (d-2) is 60% by mass or less, when heat sealing (heat sealing condition B) with the to-be-adhered film 2 and (Tmd1) or more, the to-be-adhered film 2 is strong Heat sealed.

  The melting point (Tmd2) of the low melting point resin (d-2) is preferably 50 ° C. or higher, and 60 ° C. or higher, from the viewpoint of preventing blocking between the inner and outer surfaces of the film when wound as a film. The temperature is more preferably 80 ° C. or more. The melting point (Tmd2) of the low melting point resin (d-2) is preferably 160 ° C. or less, more preferably 150 ° C. or less, and further preferably 140 ° C. or less from the viewpoint of heat sealability. preferable.

  In addition, the seal resin layer (D) 14 has a mixing ratio (d-1) of the high melting point resin (d-1) to the low melting point resin (d-2) from the viewpoint of easy peelability (d-2) Is preferably 90:10 to 20:80, more preferably 80:20 to 30:70, and still more preferably 75:25 to 50:50.

  When the seal resin layer (D) 14 functions as an easy peel layer, the easy peel strength is preferably 50 to 2000 gf / 15 mm wide. The easy peel strength is more preferably 100 gf / 15 mm or more, and still more preferably 1500 gf / 15 mm or less. By setting the width to 50 gf / 15 mm or more, necessary and sufficient adhesion is possible, and by setting the width to 2000 gf / 15 mm or less, good easy peelability (hand peeling feeling) can be obtained.

  The thickness of the sealing resin layer (D) 14 is preferably 2 μm or more, more preferably 2.25 μm or more, and more preferably 2.5 μm or more, from the viewpoint of obtaining good sealability. Is more preferably 20 μm, more preferably 10 μm or less, and still more preferably 5 μm or less, from the viewpoint of preventing film residue when acting as an easy peel layer.

(Other resin layers)
It is also possible to arrange layers other than the base material layer (A) 11, the adhesive resin layer (B) 12, the release resin layer (C) 13, and the seal resin layer (D) 14. As another resin layer, you may provide an adhesive resin layer, a barrier resin layer, an impact-resistant functional layer etc., for example.

  The said adhesive resin layer is what strengthens the interlayer strength in a multilayer film. The barrier resin layer is said to have gas barrier properties, and the resin used may, for example, be an EVOH resin, a cyclic polyolefin resin or the like. Further, the above-mentioned impact resistant functional layer is resistant to external force and pinhole property, and resins used include Ny based resins, polyester based resins and the like.

(Packaging body)
FIG. 6 is a schematic cross-sectional view at the time of sealing of the package according to the present embodiment, and FIG. 7 is a schematic cross-sectional view at the time of peeling of the package according to the present embodiment. As shown in FIG. 6, the package 3 according to the present embodiment includes a second heat seal portion 31b provided at the end of the multilayer film 1 for packaging and the film to be adhered 2, and a second heat seal portion 31b. And a first heat seal portion 31a provided outside. The second heat-sealed portion 31 b is provided by fusing the packaging multilayer film 1 and the adherend film 2 under the heat sealing condition B. The first heat seal portion 31 a is provided by fusing the packaging multilayer film 1 and the adherend film 2 under heat sealing condition A. The packaging body 3 is provided with a housing portion 23 for housing a package between the packaging multilayer film 1 and the film-to-be-adhered film 2.

  In this package 3, as shown in FIG. 7, it is possible to peel off the multilayer film 1 for packaging and the film to be adhered 2 by pinching the non-fusion part 1A provided on the outside of the heat seal part 31 of the package 3. . Thereby, in the first heat seal portion 31a, which is a region fused under the heat seal condition A, peeling is caused between the seal resin layer (D) 14 of the multilayer film 1 for packaging and the seal resin layer 22 of the adherend film 2 It can be confirmed that the peeling surface 22a is exposed and the package 3 once sealed is opened. Further, in the second heat seal portion 31b which is a region fused under the heat seal condition B, peeling occurs at the interface between the adhesive resin layer (B) 12 and the peeling resin layer (C) 13 of the multilayer film 1 for packaging It becomes possible to re-adhere the exposed surface 12A of the resin layer (B) 12 and the exposed surface 13A of the release resin layer (C) 13. Therefore, according to the package 3, by using the re-sealable packaging multilayer film 1 and combining it with the adherend film 2, it is possible to re-seal even after opening once by the heat sealing temperature, Also, it can be clearly determined that the package has been opened once. Therefore, the package 3 can be particularly suitably used for food and sanitary materials.

(Packaging container)
FIG. 8 is a view showing a specific example 1 of the packaging container according to the present embodiment, and FIG. 9 is a view showing a specific example 2 of the packaging container according to the present embodiment. The packaging container 4 shown in FIG. 8 is provided inside a first heat seal part 31 a and a first heat seal part 31 b provided on the outer peripheral part of the substantially rectangular multilayer film 1 for packaging and the adherend film 2. And a second heat seal portion 31b. Moreover, the non-fusion part 1A is provided at the corner of the outer peripheral part of the packaging container 4. The packaging container 4 shown in FIG. 9 includes a substantially rectangular multilayer film 1 for packaging, a second heat seal portion 31 b provided inside the three sides and the other side of the outer peripheral portion of the adherend film 2, and the outer peripheral portion. And a first heat seal portion 31a provided outside the second heat seal portion 31b of the other side. The non-fusion part 1A is provided on the outside of the first heat seal part 31a. The first heat seal portion 31a and the second heat seal portion 31b of the packaging container 4 are provided under the heat sealing condition A and the heat sealing condition B, respectively, as in the case of the packaging body 3 described above. Inside these packaging containers 4, the accommodating part 23 is provided between the multilayer film 1 for packaging, and the to-be-adhered film 2. As shown in FIG. In this packaging container 4, similar to the packaging body 3 described above, the resealable packaging multilayer film 1 is used, and by combining with the adherend film 2, resealing is performed even after opening once at the heat sealing temperature. It is possible to make it possible to clearly determine that the package has been opened once. In the packaging container 4, the multilayer film for packaging 1 may be used as a lid of the packaging container 4 or may be used as a bottom material.

  As described above, according to the above embodiment, the peak value of loss tangent (tan δ) of the adhesive resin layer is -35 ° C. or more, and the high melting point resin (d-1) of the seal resin layer (D) 14 The melting point difference (Tmd1-Tmd2) between the melting point (Tmd1) of the low melting point resin (d-2) and the melting point (Tmd2) of the low melting point resin (d-2) is 13 ° C. or more. While a peel function is obtained, it becomes possible to re-seal the multilayer film 1 for packaging, and the to-be-adhered film 2 in heat sealing conditions B. FIG. Therefore, it is possible to realize the multilayer film 1 for packaging, the package 3 and the packaging container 4 which can be resealed even after being opened once, and that it can be clearly judged that the opening has been made once. It becomes possible.

  Hereinafter, the present invention will be described in more detail based on examples carried out to clarify the effects of the present invention. The present invention is not limited at all by the following examples and comparative examples.

  Below, it shows about the measuring method and evaluation method of the various physical properties which concern on a present Example.

(1) Measurement of temperature showing peak value of loss tangent (tan δ) The multilayer film for packaging obtained in the following Examples and Comparative Examples was cut out into 4 mm long and 60 mm wide to prepare a sample. The obtained sample was subjected to a vibration frequency of 10 Hz, a strain of 0.1%, a temperature rising rate of 3 ° C./minute, and a distance between chucks of 25 mm using a viscoelastic spectrometer (model number: “DVA-200” manufactured by IT Measurement Co., Ltd.) Under the conditions, measurement was started from −100 ° C. in the lateral direction, and from the obtained data, a temperature showing a peak value of loss tangent (tan δ) was determined.

(2) Melting point measurement Using a differential scanning calorimeter (model number: “Pyris 1 DSC”, manufactured by Perkin-Elmer Co., Ltd.), about 10 mg of the obtained sample was heated at a heating rate of 10 ° C./minute according to JIS K7121 The temperature is raised from 40 ° C to 200 ° C, held at 200 ° C for 1 minute, then lowered to -40 ° C at a cooling rate of 10 ° C / min, and raised again to 200 ° C at a heating rate of 10 ° C / min. The melting point (Tm) (° C.) was determined from the measured thermogram.

(3) Peeling Strength Measurement and Evaluation As shown in FIG. 2, the multilayer film for packaging (X1) and the film to be adhered (Y1) or the film to be adhered (Y2) prepared in the following Examples and Comparative Examples are laminated. It heat-seals by heat seal condition A heat-sealed by melting point (Tmd2) or more and less than melting point (Tmd1), and heat-seal condition B heat-sealed by melting point (Tmd1) or more. The heat seal portion was cut into a strip shape so as to have a width of 15 mm and used as a test piece. The heat sealing time was 2 seconds, and the sealing pressure was 3.1 kg / cm ² .

About the obtained test piece, the unfused part shown in FIG. 2 is set to a testing machine using a universal testing machine (made by Intesco), and the multilayer for packaging is carried out under the conditions of tensile speed 200 mm / min and tensile angle 90 degrees. The peel strength was measured using the film (X1) and the film to be adhered (Y1) or the film to be adhered (Y2). Evaluation criteria are shown below.
○: Peeling strength is 100gf / 15mm width or more, 1500gf / 15mm width or less ×: Peeling strength is less than 100gf / 15mm width, exceeds 1500gf / 15mm width

(4) Easy peelability and re-sealability evaluation Multilayer film for packaging (X1) and film to be adhered (X1) and film to be adhered (Y1) or film to be adhered (Y2) for which peel strength evaluation was carried out for Examples and Comparative Examples in peel strength evaluation. The peeled portion was sealed at normal temperature (under 23 ° C. atmosphere), and it was confirmed and evaluated whether resealability was possible. The sealing time was 2 seconds, and the sealing pressure was 3.1 kg / cm ² .

The preparation of the test pieces was performed in the same manner as the peel strength test. The peel strength after resealing was taken as the re-peel strength by measuring the peel strength under the conditions of a tensile speed of 200 mm / min and a tensile angle of 90 degrees using a universal testing machine (manufactured by Intesco) as in the peel strength test. Under the heat sealing condition A, the easy peelability was evaluated, and under the heat sealing condition B, the resealability was evaluated. Evaluation criteria are shown below.
i) Heat sealing condition A (Easy peelability)
○: non-re-sealable, and re-peel strength less than 50 gf / 15 mm width x: re-sealable, re-peel strength more than 50 gf / 15 mm width ii) heat seal condition B (re-sealability)
○: Re-sealable, re-peel strength is 50 gf / 15 mm or more wide ×: non-re-seal, or re-peel strength less than 50 gf / 15 mm

(5) Comprehensive evaluation Based on the evaluation results of peel strength, easy peelability and re-sealability, comprehensive evaluation was performed, and the following criteria were used.
○: Evaluation of peel strength under heat sealing conditions A and B, easy peelability under heat sealing conditions A, and re-sealability under heat sealing conditions B is all ○: Peel strength under heat sealing conditions A and B, In the evaluation of easy peelability under heat sealing condition A and re-sealability under heat sealing condition B, there is a problem with at least one.

Example 1
By co-extrusion T-die method, co-extrusion is carried out under conditions of extrusion set temperature 190 ° C. or more and 230 ° C. or less, and base material layer (A) (40.5 μm) / adhesive resin layer (B) (15.0 μm) / peeling resin layer A multilayer film for packaging (X1) having a layer structure of (C) (2.0 μm) / seal resin layer (D) (2.5 μm) was produced. The film thickness was 60 μm. The layer configuration of each layer (A) to (D) and the resin material used are shown below.
[Layer Configuration of Base Layer (A) (4 Layers)]
First layer: EVOH (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “SOANOL (registered trademark)”)
Second layer: 6-66 Ny (Toray Industries, Inc., trade name "Amilan (registered trademark)")
Third layer: 6 Ny (Toray Industries, Inc., trade name “Amilan (registered trademark)”)
Fourth layer: Modified PO (made by Mitsui Chemicals, Inc., trade name "Admar (registered trademark)")
[Layer configuration of adhesive resin layer (B) (1 layer)]
Styrene-based thermoplastic elastomer (Kuraray Co., Ltd., trade name "HYBLER 7311 (registered trademark)", styrene content: 12% by mass, temperature at which a peak value of loss tangent (tan δ) is shown: tan δ value at -18.6 ° C .: 0.19)
[Layer configuration of release resin layer (C) (1 layer)]
Cyclic polyolefin resin (COC) (manufactured by Polyplastics Co., Ltd., trade name "TOPAS (registered trademark)")
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): LLDPE (manufactured by Ube Maruzen Polyethylene Corporation, trade name "Umillet (registered trademark)", Tm = 117 ° C)
Low melting point resin (d-2): EVA (manufactured by Japan Polyethylene Corporation, trade name "Novatec (registered trademark)", Tm = 89 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

  Next, amorphous polyethylene terephthalate (trade name "SKYGREEN" manufactured by SK Chemical Co., Ltd.) (220 μm) containing 32 mol% of 1,4-cyclohexanedimethanol unit in all glycol monomer units by co-extrusion method An adhesive film (Y1) used for evaluation was prepared by laminating / LDPE (manufactured by Japan Polyethylene Corporation, trade name "Novatec", used as a counterpart substrate) (20 μm). The thickness of the film to be adhered (Y1) was 240 μm.

  Next, the temperature and the melting point of loss tangent (tan δ) of the obtained multilayer film for packaging (X1), the peel strength between the multilayer film for packaging (X1) and the film to be adhered (Y1), resealability and fineness The peel strength was measured and evaluated. The evaluation results are shown in Tables 1 to 3 below.

(Example 2)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 1 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): HDPE (trade name "Novatec (registered trademark)" manufactured by Japan Polyethylene Corporation, Tm = 131 ° C)
Low melting point resin (d-2): EVA (manufactured by Japan Polyethylene Corporation, trade name "Novatec (registered trademark)", Tm = 94 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Example 3)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 1 except that the layer configurations of the peeling resin layer (C) and the sealing resin layer (D) were as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of release resin layer (C)]
Amorphous Ny (manufactured by DSM, trade name "Novamid (registered trademark), release layer D)
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): modified PO (manufactured by Mitsui Chemicals, Inc., trade name "Admar (registered trademark), Tm = 120 ° C)
Low melting point resin (d-2): EVA (manufactured by Japan Polyethylene Corporation, trade name "Novatec (registered trademark)", Tm = 94 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Example 4)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 1 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of release resin layer (C)]
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): HDPE (trade name "Novatec (registered trademark)" manufactured by Japan Polyethylene Corporation, Tm = 131 ° C)
Low melting point resin (d-2): LDPE (manufactured by Japan Polyethylene Corporation, trade name "Novatec (registered trademark), Tm = 111 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 55: 45

(Example 5)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 3 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): modified PO (trade name "Modic (registered trademark)" manufactured by Mitsubishi Chemical Corporation, Tm = 133 ° C)
Low melting point resin (d-2): LDPE (manufactured by Japan Polyethylene Corporation, trade name "Novatec (registered trademark), Tm = 111 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 55: 45

(Example 6)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 3 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): modified PO (trade name "Modic (registered trademark)" manufactured by Mitsubishi Chemical Corporation, Tm = 133 ° C)
Low melting point resin (d-2): LLDPE (manufactured by Ube Maruzen Polyethylene Corporation, trade name "Umille (registered trademark)", Tm = 117 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Example 7)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 3 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): modified PO (trade name "Modic (registered trademark)" manufactured by Mitsubishi Chemical Corporation, Tm = 133 ° C)
Low melting point resin (d-2): modified PO (manufactured by Mitsubishi Chemical Corporation, trade name "Modic (registered trademark)", Tm = 110 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Example 8)
The layer configuration of the sealing resin layer (D) was as follows, and instead of LDPE (made by Japan Polyethylene Corporation, trade name "Novatec") of the film to be adhered (Y1), homoPP (manufactured by Prime Polymer Co., Ltd.) A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 1 except that the adhesive film (Y2) was used under the trade name "Prime Polypro (registered trademark)". The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): random PP (manufactured by Prime Polymer Co., Ltd., trade name "Prime Polypro (registered trademark)", Tm = 146 ° C)
Low melting point resin (d-2): LLDPE (Mitsubishi Chemical Corporation, trade name "Modic (registered trademark)", Tm = 118 ° C)
Blending ratio of high melting point resin (d-1) to low melting point resin (d-2) = 70:30

(Example 9)
A packaging multilayer film (X1) was produced and evaluated in the same manner as in Example 8 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): homoPP (manufactured by Prime Polymer Co., Ltd., trade name "Prime Polypro (registered trademark)", Tm = 161 ° C)
Low melting point resin (d-2): random PP (manufactured by Prime Polymer Co., Ltd., trade name "Prime Polypro (registered trademark)", Tm = 146 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Example 10)
Multilayer for packaging in the same manner as in Example 3 except that the layer configuration of the seal resin layer (D) was as follows, and that the adherend film (Y2) was used instead of the adherend film (Y1). A film (X1) was produced and evaluated. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): modified PO (manufactured by Mitsui Chemicals, Inc., trade name "Admar (registered trademark)", Tm = 165 ° C)
Low melting point resin (d-2): random PP (manufactured by Prime Polymer Co., Ltd., trade name "Prime Polypro (registered trademark)", Tm = 146 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Example 11)
Multilayer for packaging in the same manner as in Example 3 except that the layer configuration of the seal resin layer (D) was as follows, and that the adherend film (Y2) was used instead of the adherend film (Y1). A film (X1) was produced and evaluated. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): modified PO (manufactured by Mitsui Chemicals, Inc., trade name "Admar (registered trademark)", Tm = 165 ° C)
Low melting point resin (d-2): modified PO (manufactured by Mitsui Chemicals, Inc., trade name "Admar (registered trademark)", Tm = 135 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 55: 45

(Comparative example 1)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 3 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of sealing resin layer (D) (1 layer)]
Denatured PO (Mitsui Chemical Co., Ltd., trade name "Admar (registered trademark), Tm = 120 ° C)

(Comparative example 2)
A multilayer film for packaging (X1) was produced and evaluated in the same manner as in Example 3 except that the layer configuration of the sealing resin layer (D) was changed as follows. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): Elastomer (manufactured by Mitsui Chemicals, Inc., trade name "Tafmer (registered trademark)", hereinafter abbreviated as "ER", Tm = 125 ° C)
Low melting point resin (d-2): LLDPE (manufactured by Tosoh Corporation, trade name "Nipolone (registered trademark)", Tm = 121 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 60: 40

(Comparative example 3)
Multilayer for packaging in the same manner as in Example 3 except that the layer configuration of the seal resin layer (D) was as follows, and that the adherend film (Y2) was used instead of the adherend film (Y1). A film (X1) was produced and evaluated. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of sealing resin layer (D) (1 layer)]
Denatured PO (Mitsui Chemical Co., Ltd., trade name "Admar (registered trademark), Tm = 135 ° C)

(Comparative example 4)
Multilayer for packaging in the same manner as in Example 3 except that the layer configuration of the seal resin layer (D) was as follows, and that the adherend film (Y2) was used instead of the adherend film (Y1). A film (X1) was produced and evaluated. The evaluation results are shown in Tables 1 to 3 below.
[Layer configuration of seal resin layer (D) (1 layer: mixed resin of high melting point resin (d-1) and low melting point resin (d-2))]
High melting point resin (d-1): random PP (manufactured by Prime Polymer Co., Ltd., trade name "Prime Polypro (registered trademark)", Tm = 146 ° C)
Low melting point resin (d-2): modified PO (manufactured by Mitsui Chemicals, Inc., trade name "Admar (registered trademark)", Tm = 135 ° C)
Mixture ratio of high melting point resin (d-1): low melting point resin (d-2) = 55: 45

  As can be seen from Tables 1 to 3, according to the multilayer film for packaging according to the above embodiment, the evaluation of the heat sealing condition A and the heat sealing condition B of the package formed by heat sealing with the adherend film Both were ○, and the overall evaluation was ○ (Examples 1 to 11). From these results, in Examples 1 to 11, the heat sealing condition A functions as an easy peel, and the heat sealing condition B enables resealing, so it is clearly determined that the packaging multilayer film was opened at one time. It is possible. Therefore, according to the multilayer film for packaging which concerns on the said embodiment, resealable with the other-parts base material after opening once is possible, and for resealable packaging which it can judge clearly that opening once is possible. It can be seen that multilayer films and packages can be realized.

  On the other hand, in Comparative Examples 1 to 4, the overall evaluation was x. When the sealing resin layer of the multilayer film for packaging was a single resin, the peel strength evaluation was x under the heat sealing condition A, and the sealing was impossible (Comparative Example 1, Comparative Example 3). It is considered that this result is because the sealing resin layer does not contain at least two or more resins having different melting point differences, and the sealing temperature is low under the heat sealing condition A. In addition, even if the sealing resin layer contains at least two or more kinds of resins having different melting point differences, if the melting point difference is less than 13 ° C., under the heat sealing condition A, partial resealing is possible, It could not be clearly confirmed that the container was opened once (comparative example 2, comparative example 4). It is considered that this result is due to the fact that the difference in melting point is small, so that even in the heat sealing condition A, partial resealing has become possible.

DESCRIPTION OF SYMBOLS 1 multi-layer film for packaging 1A non-fusion part 2 bonded film 3 package 4 package container 11 base material layer 12 adhesive resin layer 12A exposed surface 13 release resin layer 13A exposed surface 14 seal resin layer 21 base material layer 22 seal resin layer 22a peeling surface 23 accommodation portion 31 heat seal portion 31a first heat seal portion 31b second heat seal portion

Claims (10)

The base material layer (A), the adhesive resin layer (B), the release resin layer (C) and the seal resin layer (D) including at least four layers laminated in this order,
The adhesive resin layer (B) is mainly composed of a styrene-based thermoplastic elastomer having a peak value of loss tangent (tan δ) measured at a frequency of 10 Hz by dynamic viscoelasticity measurement at -35 ° C. or higher,
The seal resin layer (D) contains a resin composition in which at least two types of a resin (d-1) and a resin (d-2) are mixed,
The packaging multilayer, wherein the melting point difference (Tmd1-Tmd2) between the melting point (Tmd1) of the resin (d-1) and the melting point (Tmd2) of the resin (d-2) is 13 ° C. or more the film.   The multilayer film for packaging according to claim 1, wherein a content of each of the resin (d-1) and the resin (d-2) in the resin composition is 25% by mass or more.   The packaging multilayer film according to claim 1 or 2, wherein in the sealing resin layer (D), the resin (d-1) and the resin (d-2) each contain a polyolefin resin.   The said base material layer (A) contains at least 1 layer which has at least 1 sort (s) selected from the group which consists of ethylene-vinyl acetate copolymer saponification thing and a polyamide-type resin as a main component. The multilayer film for packaging according to any one of 3.   The packaging according to any one of claims 1 to 4, wherein the release resin layer (C) contains as a main component at least one selected from the group consisting of polyamide resins and cyclic polyolefin resins. Multilayer film.   The multilayer film for packaging according to any one of claims 1 to 5, wherein a thickness of the sealing resin layer (D) is 2 μm or more and 20 μm or less.   A package comprising the multilayer film for packaging according to any one of claims 1 to 6.   The package according to claim 7, which is for food.   The package according to claim 7, which is for sanitary materials.   A packaging container comprising the packaging body according to any one of claims 7 to 9.

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